Transcript PowerPoint Presentation - Outcome after interventional or

Outcome after interventional or conservative
management of unruptured brain arteriovenous
malformations: a prospective, population-based cohort
study
Lancet Neurol March 2008
Sajedha Mahmood
Background
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AVMs are leading cause of ICH in young adults, but ICH is presenting
symptom in only half of AVM diagnoses
Increased detection of incidental, asymptomatic AVMs due to improved
imaging
Unruptured AVMs can be treated by intervention to avoid future rupture
Risk of complications vs risk of conservative treatment
Columbia AVM Databank analysis shows that outcome after
intervention for unruptured AVM worse than conservative management
Currently ARRUBA (randomised trial of unruptured brain AVMs)
ongoing
This study compares functional outcome of adults with unruptured AVM
following intervention vs observation
Prospective, population-based cohort study
Methods
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Scottish Intracranial Vascular Malformation Study (SIVMS)
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Demographic data: age, sex, socioeconomic status
Clinical data: type of presentation, comorbidities, smoking status, Oxford
Handicap scale at presentation
Neuroradiological data: first diagnostic imaging assessed by 2 neuroradiologists
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Register of patients > 16 years when first diagnosed with any unruptured intracranial
vascular malformation
Data from 1999 - 2003
Follow-up data accrued until analysis date 1 October 2007
AVM size, venous drainage pattern, function of adjacent brain area, Spetzler-Martin
grade, deep brain location, AVM-associated aneurysms
Intervention defined as any type of intervention on AVM or associated aneurysm
AVM nidus obliteration confirmed by DSA or MRA
Methods
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Follow-up: annual OHS ratings provided by GP
Annual survey of medical records for occurrence of ICH, infarction or
focal neurological deficit
ICH: defined as symptomatic clinical event with signs of ICH on
imaging, in CSF or post mortem
Independent investigator assessed death, infarction, FNDs on basis of
medical records, imaging and pathology
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Unaware of prognostic features
Analysis
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Comparison of demographic, clinical, radiological characteristics
Survival analysis:
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OHS scores 0-1 vs 2-6 (2= some restrictions to lifestyle, but able to look
after themselves)
Time from presentation onwards for conservative management group
Time from first intervention for treatment group
Results
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229 adults with AVMs
114 presented with unruptured aneurysm
63 of 114 (55%) - interventional treatment - type of treatment decided
by local clinician
51 (45%) - observation
7 patients treated had ICH/infarct/FND between presentation and
intervention
Treatment began a median of 1 year after presentation
AVM nidus completely obliterated in 42 (67%), partially in 19 (30%), no
data available for 2 (3%)
2 deaths within 3 years after treatment: one partially obliterated AVM
post embolisation, other after radiosurgery with obliterated AVM on
imaging few weeks prior to ICH
4 deaths in untreated group: one SAH, others unrelated causes
Progression to first ICH, infarction, FND
Progression to sustained poor outcome
Progression to poor functional outcome
Conclusions
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Intervention and AVM size are predictors of progression to poor
outcome (OHS 2-6) in first 3 years
No difference in progression to OHS 2-6 that is sustained until end of
year 3 in both arms
No difference in overall spectrum of dependence
Discussion
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Thorough case evaluation
Prospective annual follow-up
Blinded assessment of outcomes
Comparison between treated vs untreated
OHS as outcome measurement
Prospective cohort study
Baseline imbalance between both groups
DSA data not available for all patients
Short-term follow-up
Follow-up by GPs rather than neurologist/neurosurgeon